It is a desirable feature to have a complete guard enclosure surrounding a work chamber of a machining center, to contain chips and coolant. In production machining centers, it is frequently desirable to provide for a pallet exchanger where a first pallet supported workpiece may reside within the work chamber, while a second pallet is at an operator service station outside the work chamber. The second pallet is mounted with a new, rough workpiece, and, at the end of a machining cycle, the pallets are interchanged with one another, usually by automatic means having either a linear or rotary path.
As machines and pallets increase in size, the guard enclosure can become so large as to inhibit operator access to the work zone for purposes such as inspection and measurement at prescribed times during a machining cycle.
An access door may be placed in the guard enclosure for the operator to carry out prescribed tasks, and the present invention thus concerns itself with provision of an access door in a guard enclosure which will tend not to increase the size of a guard which provides comparable enclosure but does not have an operator access door.